Scientists warn that anthrax, a deadly bacterium that can be fatal if left untreated, may be lurking silently beneath some American homes and in the surrounding soil.
This bacterium, scientifically known as Bacillus anthracis, causes dark blisters and sores, and can be fatal in most cases if not treated promptly. Although most Americans believe they will never be exposed to it, scientists confirm that the bacteria are present in large swaths of American soil, particularly in the topsoil, which is less than 15 centimeters deep.
“The bacteria that cause anthrax remain underground, settling around plant roots and interacting with nearby microorganisms,” said Hannah Kinzer, a doctoral student in public health at Washington University in St. Louis.
Many people picture anthrax as a white powder, as it appeared in the biological attacks of 2001, but in reality the bacteria are invisible to the naked eye and often remain dormant in the soil, especially in pastures and old burial sites.
Large herbivores such as cattle and deer are infected by ingesting spores found in the soil or through wounds and scratches. Once the bacteria enter the animal's body, they cause severe internal bleeding, leading to death within 48 hours. The spores then return to the soil, completing their life cycle.
Human infection is usually accidental and rare, as transmission requires exposure to a large number of spores through the skin, inhalation, or ingestion, such as by handling the hides and wool of infected animals or consuming undercooked meat. No direct human-to-human transmission has been recorded.
Symptoms appear one to two months after exposure and include small, itchy blisters and painless sores on the face, neck, or arms, along with excessive sweating, chest pain, and redness of the face and eyes. If left untreated, the condition can progress to life-threatening complications such as sepsis or internal bleeding.
Infections can be treated with antibiotics for 60 days or by receiving a three-dose anthrax vaccine, but the effectiveness of the treatment varies depending on the method of infection, with the survival rate reaching about 55% in cases of inhalation, and 60% in cases of ingestion, while skin infections almost completely heal.
Kinzer notes that the bacteria prefer soil rich in alkaline substances, calcium, and nitrogen, but they can remain dormant in the soil as spores for up to 50 years or more, awaiting suitable conditions to become active. Eradicating them is difficult due to their resistance to drought, radiation, and chemicals.
